Question

Supposed I register many different function names in Lua to the same function in C. Now, everytime my C function is called, is there a way to determine which function name was invoked?

for example:

int runCommand(lua_State *lua)
{
  const char *name = // getFunctionName(lua) ? how would I do this part
  for(int i = 0; i < functions.size; i++)
    if(functions[i].name == name)
      functions[i].Call()
}

int main()
{
  ...

  lua_register(lua, "delay", runCommand);
  lua_register(lua, "execute", runCommand);
  lua_register(lua, "loadPlugin", runCommand);
  lua_register(lua, "loadModule", runCommand);
  lua_register(lua, "delay", runCommand);
}

So, how do I get the name of what ever function called it?

Answer 1

Another way to attack your question is by using upvalues. Basically, you register the C functions with the function below instead of lua_register:

void my_lua_register(lua_State *L, const char *name, lua_CFunction f)
{
      lua_pushstring(L, name);
      lua_pushcclosure(L, f, 1);
      lua_setglobal(L, name);
}

Then, getFunctionName is straight forward

const char* getFunctionName(lua_State* L)
{
    return lua_tostring(L, lua_upvalueindex(1));
}

That said, what you trying to do seems fishy – what are you trying to achieve? The runCommand function posted in the question looks like a horribly inefficient way to do something that Lua does for you anyway.